The Summary of the Secure Egg Supply (SES) Plan
The SES Plan promotes food security and animal health through continuity of market planning for a highly pathogenic avian influenza (HPAI) outbreak. This plan makes specific science- and risk- based recommendations that emergency decision makers (such as Incident Commanders) can use to rapidly decide whether to issue or deny permits for the movement of egg industry products during an HPAI outbreak.
The Egg Sector Working Group—a multidisciplinary team—prepared the SES plan. This team includes the following:
- University of Minnesota, Center for Animal Health and Food Safety
- Iowa State University, Center for Food Security and Public Health
- United Egg Producers
- Egg sector veterinarians and officials
- State officials
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services (USDA APHIS VS)
HOW THE SES PLAN WORKS
The SES Plan is based on current research and practice in fields including virology, flock husbandry, epidemiology, and risk-assessment. The SES plan uses science- and risk-based preparedness and response components (see figure below) to provide guidance on permitting the movement of egg industry products from a Control Area during an HPAI outbreak. Simultaneously, these recommendations effectively manage the risk of HPAI transmission to naïve premises. Through the integrated implementation of the components listed in the figure below, this plan provides a high degree of confidence that egg industry products moved into market channels do not contain HPAI virus.
Summary of SES Plan Testing Requirements for Product Movement
The surveillance recommendations for real-time reverse transcriptase polymerase chain reaction (RRT-PCR) testing for poultry within an HPAI Control Area are based on guidance prepared by the APHIS Centers for Epidemiology and Animal Health (CEAH), National Surveillance Unit. Guidance on observational surveillance, including the mortality threshold and clinical signs, is based on information provided by the Egg Sector Working Group and proactive risk-assessment team at CEAH.
MORTALITY PRODUCTION PARAMETERS
Flocks are to be monitored daily for obvious signs and symptoms of disease. An increase in mortality is daily mortality greater than 3 times the past 7-day average and greater than 0.03 percent. Flocks that do not display such signs and have no apparent increase in mortality will be monitored by RRT-PCR testing or another suitable procedure, as determined by Incident Command.
RRT-PCR testing of one 5-bird pool sample from dead or euthanized sick birds per 50 dead on each house on the premises. Movement of products may require negative RRT-PCR tests, as indicated in the product specific summaries. When a hold is required for movement, at least one of the two required RRT-PCR tests must be taken on the second day of holding or later.
A State or Federal regulatory official or an individual authorized by Incident Command takes five oropharyngeal swabs from 5 dead chickens per house and the swabs (5) are pooled in a tube containing brain-heart infusion (BHI) broth. Sampling and disposal should be completed in a biosecure manner. The samples are submitted to an authorized State veterinary diagnostic laboratory. Veterinary diagnostic laboratory personnel perform RRT-PCR testing on samples immediately upon receipt and transmit the results to the Incident Command on the same day. The Incident Command reports the tests results to the farm manager. If the test is not negative or if daily mortality spikes over 3 times the past 7-day average, additional diagnostic testing will be conducted.
IMPORTANT NOTE ON DIAGNOSTIC TESTING
The RRT-PCR test is not a pathotyping assay, and cannot separate HPAI and LPAI strains. However, RRT-PCR testing can be used as a means to know that targeted avian influenza strains (both low and high pathogenicity) are present if there is a positive RRT-PCR. All mention of RRT-PCR testing in the SES Plan is in reference to surveillance for HPAI in an outbreak situation, after HPAI has been characterized by virus isolation and/or other pathotyping assays. If positive RRT-PCR tests are obtained with no confirmation of illness or mortality, further pathotyping will be conducted to determine the presence of HPAI.